44° Journal of Agriculture . [loJuLV, TQ09. 



which had not a bitter taste. It is also interesting to note that in con 

 nexion with the disease so named, he had seen no evidence that wouM 

 pro'\e the disease to be caused bv a fungus. 



The latest from America in connexion with this disea.se is by Brook> 

 in the BuUetiu of the Torre v Botanical Club for September, 1908, on 

 ' The Fruit Spot of Apples." The writer states that there are two dis- 

 tinct fruit spots occurring on the apple, one of which is called the " Fruit 

 Pit "' and the other the " Fruit Spot," the latter being associated with 

 a distinct fungus. 



It is the former which agrees with our •' Bitter Pit," although the 

 writer was unable to detect a bitter taste in the browned tissue. With 

 regard to the cause and occurrence of the disease he writes : — " Micro- 

 scopical examination of fruit pits have given no indication of the pre- 

 sence of fungi or bacteria. Brown tissue from the surface pits and from 

 the more deeply seated vascular regions has been transferred to various 

 culture media but always without securing bacterial or fungus growth." 



Although the cause is unknown, the disease it.self has characteristic 

 symptoms and these, together with its distribution and varieties affected, 

 will be given as a necessary preliminary to the recommendations to be 

 made for dealing with it. 



Symptoms. — In some varieties the external indications appear while 

 the fruit is still on the tree, and in others they only appear after the fruit 

 is picked and stored. In the case of " Prince Bismarck " I have seen 

 fully 90 per cent, of the fruit "pitted" while on the tree and in the 

 case of Jonathans they may appear sound when shipped and the disease 

 develops on the voyage. Whether de\eloped on the fruit on the tree or 

 in .storage, however, there is no mistaking the appearance presented bv the 

 di.sease. Numerous small depressions, somewhat hemispherical in shape, 

 usually appear on the surface of the apple, and on examining the tissue 

 beneath these sunken areas the cells are found to be brown and shrunken 

 thus accounting for the depressions. The spots ultimately become dark 

 brown appearing almost black, and several of them mav run together to 

 form one large spot. This spotting of the surface is usually accompanied 

 by an internal brow'uing of the tissue. When the fruit is cut across 

 numerous isolated brown spots are seen, hut when carefully examined these 

 are found to be in reality continuous strands of brown tissue surrounding 

 the vascular bundles. The surface spots may occur without the internal 

 browning and the di.sease is then sometimes distinguished as " surface 

 pit," and the internal browning may occur without anv evident surface 

 markings. I have found both the outer and inner brown tissue to have a 

 bitter taste when kept in the mouth for a short time, but some good obser- 

 vers have failed to detect it. In the case of pears the bitterness is vers 

 pronounced, resembling that of quinine. 



Distribution. — The disea.se known as '" Bitter Pit " or " Fruit Pit '" 

 not only occurs in Australia but has been found in the United States of 

 America, Canada and Cape of Good Hope. It is also well known in Ger- 

 many where it is called " Stippen " from its supposed resemblance to the 

 dots u.sed in strippling bv artists. In the Australian States, it has been 

 the cause of severe losses for some years past in Victoria, New South 

 Wales, South Au.stralia and Tasmania, and the disease will probabK 

 loecome trouble.some in the other States as the fruit-growing area is 

 extended. 



Varieties Affected. — The pear and quince are known to be affected 

 by this di.sease, Init it is in the apple that it is be.st known and has done 



